AC blowing warm air caused by a bad PCM??
08-13-2003, 12:26 PM
#1
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Location: LA, So Cal
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AC blowing warm air caused by a bad PCM??
i just spent $75
for AC and electrical diagnose. they told me that the cause of my AC blowing warm air, is because my chip is going bad, i told them, i dont have any chips
. then, they tried to explain that my ECM is fried. is this true?? can a fried pcm or ecm cause this?? my car has been running great, not one problem. i would suspect that a bad ECM or PCM would make my car run like crap, or might not even run at all. any advice or information on this before i take this matter somewhere else. i dont want to spend another dime for a useless diagnose again. thanks guys
PS: this is my bad month. money coming out for nothing (sorry i just need to relieve the pressure
)
for AC and electrical diagnose. they told me that the cause of my AC blowing warm air, is because my chip is going bad, i told them, i dont have any chips . then, they tried to explain that my ECM is fried. is this true?? can a fried pcm or ecm cause this?? my car has been running great, not one problem. i would suspect that a bad ECM or PCM would make my car run like crap, or might not even run at all. any advice or information on this before i take this matter somewhere else. i dont want to spend another dime for a useless diagnose again. thanks guysPS: this is my bad month. money coming out for nothing (sorry i just need to relieve the pressure
)
08-13-2003, 12:32 PM
#3
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Originally posted by 94ZGRNMCHN
Try some freon bud.get it tested for leak's.
Try some freon bud.get it tested for leak's.
now
08-13-2003, 03:58 PM
#5
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Join Date: Oct 2002
Posts: 496
Get a A/C do-it-yourself kit at Walmart for $25. Be sure to add to low pressure valve.
My A/C was blowing warm, I know it has a leak not worth fixing, I added freon and it will be fine for the rest of the summer. It's ice cold now.
Next summer I'll add another can for $10.
My A/C was blowing warm, I know it has a leak not worth fixing, I added freon and it will be fine for the rest of the summer. It's ice cold now.
Next summer I'll add another can for $10.
08-13-2003, 06:44 PM
#6
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are you guys sure that this is caused by the freon?? because the AC guys that checked my car today said that the kompressor or the condensor is not working caused by a bad PCM.
i'm not sure if they know what they are doing, so i just paid $75 and took off.
i'm not sure if they know what they are doing, so i just paid $75 and took off.
08-13-2003, 08:00 PM
#8
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Location: Lexington ,Ky
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My A/C wasnt working either. Car had been sitting 3 years.Put freon in but had to jump compressor relay on to get it to take.After up to pressure still not kicking in on its own but getting very cold when jumped on .Next day started checking wiring from ecu. Found no sig to relay out of ecu. wire ok to relay coil. Hooked back up ,just about to go to dealer and started to work.I ve read around and output from ecu to relay has gone bad before.Maybe ECU connection, try cleaning.
08-13-2003, 08:00 PM
#9
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Posts: 496
One last comment, compressor will stop working if coolant level is too low.
When I was doing a prepurchase inspection, the compressor did not kick on. However, when the mechanic added freon - it worked!
I was told they could fix the leak (w/o much of a warranty) but most likely the leak would come back w/in a year or so.
Therefore, I choose to add freon when I need it. The kit is safe and simple.
When I was doing a prepurchase inspection, the compressor did not kick on. However, when the mechanic added freon - it worked!
I was told they could fix the leak (w/o much of a warranty) but most likely the leak would come back w/in a year or so.
Therefore, I choose to add freon when I need it. The kit is safe and simple.
08-13-2003, 08:05 PM
#10
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Join Date: Nov 2001
Location: West Palm Beach, FL
Posts: 646
The PCM turns the compressor on and off while you're using the A/C. If it's not kicking on, then that may be caused by the PCM. But if your PCM is bad, I would think it would affect more than just the A/C.
08-14-2003, 12:18 AM
#11
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Originally posted by Mikey97Z
The PCM turns the compressor on and off while you're using the A/C. If it's not kicking on, then that may be caused by the PCM. But if your PCM is bad, I would think it would affect more than just the A/C.
The PCM turns the compressor on and off while you're using the A/C. If it's not kicking on, then that may be caused by the PCM. But if your PCM is bad, I would think it would affect more than just the A/C.
Originally posted by RKB4C
One last comment, compressor will stop working if coolant level is too low.
When I was doing a prepurchase inspection, the compressor did not kick on. However, when the mechanic added freon - it worked!
I was told they could fix the leak (w/o much of a warranty) but most likely the leak would come back w/in a year or so.
Therefore, I choose to add freon when I need it. The kit is safe and simple.
One last comment, compressor will stop working if coolant level is too low.
When I was doing a prepurchase inspection, the compressor did not kick on. However, when the mechanic added freon - it worked!
I was told they could fix the leak (w/o much of a warranty) but most likely the leak would come back w/in a year or so.
Therefore, I choose to add freon when I need it. The kit is safe and simple.
Last edited by TMDZ28; 08-15-2003 at 02:18 AM.
08-15-2003, 03:00 AM
#13
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Join Date: Feb 2001
Location: Cincinnati, Ohio
Posts: 3,068
It is possible that the ECM is causing the havoc. I dont know the full details because i wasnt present when the car was being worked on, BUT.....
My dads 383 imp SS air stopped working one day. System was fully charged, and yet it would only blow hot air. I had no idea what was going on, so i suggested he take it to my buddy. He took it out to lt1 dave (lt1 guru and the buddy of mine) who originally did the programming on the car. Even though the program hadnt been recently touched, there was something corrupt within the program allowing the AC to not work properly. He took a totally new BIN file (didnt d/l the program in the car because then it would still be corrupted) and reflashed the ecm. Presto, ac worked. As i said, i wasnt there for explanation, but thats what i heard from my father.
AS for your car, it cant hurt to grab a different BIN file from the net, modify it to your car, and re-flash. See what happens then...
My dads 383 imp SS air stopped working one day. System was fully charged, and yet it would only blow hot air. I had no idea what was going on, so i suggested he take it to my buddy. He took it out to lt1 dave (lt1 guru and the buddy of mine) who originally did the programming on the car. Even though the program hadnt been recently touched, there was something corrupt within the program allowing the AC to not work properly. He took a totally new BIN file (didnt d/l the program in the car because then it would still be corrupted) and reflashed the ecm. Presto, ac worked. As i said, i wasnt there for explanation, but thats what i heard from my father.
AS for your car, it cant hurt to grab a different BIN file from the net, modify it to your car, and re-flash. See what happens then...
08-15-2003, 08:09 AM
#15
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Location: Landover, Maryland
Posts: 153
When I bought my 94 Z, my A/C wasn't working either. It turns out I had a four-fold problem. #1, I was out of freon. #2, my pressure switch was bad. (Verified by jumping the pressure switch and hearing 'click click' as the compressor turned on and the engine revved up, turning the fans on). #3, I had a leak in my blowoff valve, which was replaced at around $15 or so. #4, and this is the most important part, because I was low on R134, the PCM had "blocked out" my A/C compressor. All I did was disconnect the negative battery cable for about 5 seconds and reconnect it, it reset my PCM and my A/C blew ice cold. Chances are, you have a leak, you're out of freon, and the computer won't allow your A/C to kick on because it's trying to save your compressor. Just a thought.